Processing facilities are often managed using industrial control and automation systems. Example processing facilities include chemical, pharmaceutical, paper, and petrochemical production plants. Among other operations, industrial control and automation systems typically interact with and control industrial equipment in the processing facilities, such as equipment used to produce chemical, pharmaceutical, paper, or petrochemical products.
Industrial control and automation systems routinely include wired components and wireless components, such as wireless sensor networks that provide data to wired controllers. A typical wireless sensor network (such as one that operates according to an IEEE 802.11 standard) includes battery-powered sensor devices and line-powered access points. The access points typically provide access to a wired network, such as an Ethernet network.
Since each sensor device in a typical wireless sensor network communicates with a single access point, this increases the likelihood of unreliable communications in the wireless network. This reduces the overall reliability of the 802.11-based wireless network, particularly for applications involving critical or low latency data. Moreover, the transmission power of the sensor devices typically cannot be increased to provide greater reliability since the sensor devices are typically battery-powered (and any increase in transmission power results in a corresponding increases in power consumption).